I was interested in reformating because the card I have been using one day started having a problem when viewing the images from the camera display, as I scrolled thru the pics a big ? would come up. I cycled the power on the camera and it was fine after that. So, when I got home I uploaded the pictures and reformated the card with the utility in the camera and all was fine. I was just wondering if all the shots I was taking and deleting if it was just too much for the card (I know how file storage works) or the camera to save around on the file-table.

I have shot about 400 images at each of a couple of soccer matches, with my first Canon 7D. I shot well over 400 images with two Canon Digital Rebel XTi (400D) cameras at a complex crime scene.

At work, I use 2GB Sandisk CF cards. For my personal use, I use Delkin 4 and 8 GB Combatflash CF cards.

If one is blistering one's index finger, one is mashing the shutter release button with too much force, I would think. That would likely send tremors through the camera.

Without sitting down and trying to figure the totals, I would estimate having shot several thousand images since July 2010 with five Canon DSLR cameras, at work and on my own time, with my job's images being the majority.* From 2009 to July 2010, I probably shot a few hundred, at most, with Sony and Olympus point-and-shoot cameras. Before 2009, my digital
photography was limited to occasional shots with mobile phones.

*I do not consider myself a "pro" photographer; I am a licensed professional peace officer with the recently-added responsibility of photography. My experience level is, by my estimate, serious beginner.

I use four different cards, my two main cards are class 6 SanDisk, each one 4 GB. When I fill those, I switch to my two 8 GB Lexar cards, each class 6 (but slower). Those seem to do fine, as I have a bad habit of deleting my pictures in the field, I have a tendency to chimp after shooting (it's bad habit, but it frees up a fair bit of space on my card, plus it lets me get rid of the shots that I already know are terrible and unsalvageable. According to my EXIF data I've taken some 19 000 photos with my D7000.

By the way, here's a quick tip for checking how many shutter actuations you've taken with your camera, if you go into playback (at least on Nikon cameras) the photo's name, ex. DSC-3928, is the thousand digit of how many photos that you've taken. So if you know that you've at least taken 40 000 and the image's name is DSC-3928, then it's your 43 928 shutter actuation.

I used my friends Nikon D40 not new, took a lot of pics in Raw and started with DSC_0001 and so on then changed it to shoot Jpeg and
started with DSC_0001 and so on, how ever there were a few already on the memory card which I did not upload, so do you think it could be my software on this computer that catalogs them? I openend them in photoshop.
My Sony was new and it started with DSC_0001 now on DSC_00600 so if I put them on another computer would it start back at DSC_0001 ?

off-topic: what's this fab with people writing the plural wrong (ex: "camera's" instead of "cameras")? I've seen it a lot lately.

on-topic: I have 2 4GB cards for my 10mpx camera,which I consider enough,I don't shoot more than 100-200 shots per session. Plus,I transfer all my photos to my backup locations once the session is over & I arrive home to start editing them. For specific events,I always recommand people at least 2 8GB cards & also advice them to not be "shutter-happy",because that way they'll not get better & they could aqsually miss a good moment.

off-topic: what's this fab with people writing the plural wrong (ex: "camera's" instead of "cameras")? I've seen it a lot lately.

It's a gross misuse and misunderstanding of the apostrophe, much like when people write your instead of you're i.e. you are. Now a lot of people misuse the apostrophe when they indicate a person doing something e.g. He make's me laugh (I just felt dirty doing that).

Many errant apostrophes, though certainly not all, are put here by the auto-fill/auto-correct in iPads. I spend much time removing them.

Regarding the question on why had used so many cameras, well it is a combination of having started with a borrowed XTi/400D, soon acquiring my own pre-owned XTi, then quickly realizing the advantages of a 40D or 50D, with the result of acquiring a pre-owned 40D. Soon afterward, when I was assigned to do some aerial shooting, I realized the 7D would have some advantages, especially as a colleague, with whom I shared the assignment, was using a 7D. So, my upgrade schedule was very quick. One XTi was traded for credit on a lens purchase.

The difference in placement of controls on the 40D and 7D resulted in occasional confusion, so when a chance arrived to acquire a gently-used, pre-owned 7D, I acquired my second 7D. I like having two cameras with me at work.

Also, my wife is a photographer. I started with her XTi, which has reverted to being a family camera. She had previously used an agency-issued 40D at her job, and is comfortable with its controls, so my 40D has also become a family camera.